<?php 
   
  /** 
   * 抽象處理者角色 
   * @author wzy 
   * 
   */ 
  abstract class Handle 
  { 
   
    /** 
     * 持有后繼的責(zé)任對(duì)象 
     * 
     * @var object 
     */ 
    protected $successor; 
   
    /** 
     * 示意處理請(qǐng)求的方法，雖然這個(gè)示意方法是沒(méi)有傳入?yún)⑺氐?
     * 但實(shí)際是可以傳入?yún)?shù)的，根據(jù)具體需要來(lái)選擇是否傳遞參數(shù) 
     */ 
    public abstract function handleRequest (); 
   
    /** 
     * 取值方法 
     * 
     * @return object 
     */ 
    public function getSuccessor () 
    { 
      return $this->successor; 
    } 
   
    /** 
     * 賦值方法，設(shè)置后繼的責(zé)任對(duì)象 
     * 
     * @param object $objsuccessor       
     */ 
    public function setSuccessor ($objsuccessor) 
    { 
      $this->successor = $objsuccessor; 
    } 
  } 
   
  /** 
   * 具體處理者角色 
   * 
   * @author wzy 
   *     
   */ 
  class ConcreateHandler extends Handle 
  { 
   
    /** 
     * 判斷是否有后繼的責(zé)任對(duì)象 
     * 如果有，就轉(zhuǎn)發(fā)請(qǐng)求給后繼的責(zé)任對(duì)象 
     * 如果沒(méi)有，則處理請(qǐng)求 
     * 
     * @see Handle::handleRequest() 
     */ 
    public function handleRequest () 
    { 
      if ($this->getSuccessor() != null) { 
        echo "放過(guò)請(qǐng)求，將請(qǐng)求轉(zhuǎn)發(fā)給后繼的責(zé)任對(duì)象!<br>"; 
        $this->getSuccessor()->handleRequest(); 
      } else { 
        echo "處理請(qǐng)求，處理過(guò)程省略...<br>"; 
      } 
    } 
  } 
   
  /** 
   * 客戶(hù)端代碼 
   */ 
   
  // 組裝責(zé)任鏈 
  $handle1 = new ConcreateHandler(); 
  $handle2 = new ConcreateHandler(); 
  $handle1->setSuccessor($handle2); 
   
  // 提交請(qǐng)求 
  $handle1->handleRequest(); 
  ?>